Presentation on theme: "Population and the Environment"— Presentation transcript:
1 Population and the Environment Chapter 21Gene DeMaio
2 Demography – The Study of Population Is studied extensively by scientists in many different types of fieldsBiologists study factors that effect fertilityMedical scientist analyze causes of deathSociologists study factors that effect population trendsSocial Norms and values that effect mortality and fertility such asFertility (level of reproduction) – laws, religious and moral valuesMortality (level of death) – nutrition, health care, living conditionsDemographers observe components of a population (size, density, distribution, stratification) to try to predict and understand reasons for change in a population
3 Studying the Population today Main way of gathering info about the population is a Census,required by the U.S. every 10 yearsCensus is a counting of a populationCensuses are aided by vital statistics, records of births, deaths, marriages, & divorcesPopulations in developing nationsLeading Cause of death among children in developing nations is Malnutrition18% of children in these nations die before age five (11x the percentage in developed nations)Controlling the population of these nations may be linked to reducing hunger
4 Thomas MalthusBelieved that the world population was growing faster than the food supply.The gap between the food supply and the population would continue to grow until thee was nowhere near enough food to feed the population.Supported controlling population growth, but denounced Birth control.Went against the churchInstead he said to postpone the age people marry and limit the number of children that are born
5 Karl Marx Disagreed with Malthus ?Karl MarxDisagreed with MalthusIn an ideal society an increase in population would lead to greater wealth due to an increased work force.Capitalism did not operate under these conditions, they used financial resources on building skyscrapers and roads rather than for housing and equal distribution of foodHe did believe that communism would operate under these conditions
6 Demographic Transition A rapid decline in deathrates followed by a dramatic increase in population.A natural part in the development of nations.Occurs in three phases:Pre-Transition – High birthrates, High deathrates, Little population growthTransition – Deathrates decrease sharply, birthrates stay high, significant population growthPost-Transition – Birthrates decrease, Deathrates stay low, little population growth.Drop in deathrates can be caused by improvements in Healthcare and living conditions
7 Population Explosion A rapid increase in the world population The world population has grown nearly 7x more in the past 200 years than it had in all of previous history of the earthCould lead to side effects predicted by MalthusCounties have supported birth control and family planningChina enforces a strict one child per family law. This leads to a decrease in population
8 Population Pyramid, Momentum of Population Growth
9 Baby Boom After WWII, Birthrates began to dramatically increase. Death rates decreased after the warSoldiers had been separated from there wives for very long, post war economy encouraged purchasing homes and having children.Fertility rate eventually declinedDemographic TransitionLead to momentum for further growth
10 Zero Population Growth (ZPG) After the Baby boom fertility rates drastically decreasedAlthough birthrates are still greater than deathrates in the US, sociologists have predicted a possible state of ZPGThe # of deaths = the # of births and the # of immigrants = the # of emigrants?
11 Possible economic affects Greater proportion of elderly (75+)Greater demand for Health care and Social ServiceLow fertility rates would lead to women spending fewer years raising children and could increase the proportion of married women in the workforceLeads to an increased work force and a more stable economy
12 Migration 2 types of Migration, Internal and International. International – from country to countryCould be caused by a poor economy in the home country as well as a strong one in the new one. Ex. Potato famine in IrelandWars/Political problems in the homeland. Ex. End of Communism lead to a migration from former USSR to western Europe.Is limited by the government,Internal Migration – within a countryCan be caused by greater job opportunities in a new state.Industrialization led to migration to citiesClimate – since the 70’s a significant amount of the population has moved from the “Snow Belt” (New England, NY, Ohio, Chicago ect.) to the “Sun Belt” (NC, Florida, Arizona ect.)Is not at all controlled by gov’t
13 Human Ecology Interrelationships between people and their environment Natural environment serves three basic functions for humans:Provides the resources essential for lifeServes as a waste repositoryHouses our species
14 Conflict View of the Environment Less developed nations are being forced by powerful industries to exploit their natural resources such as fisheries, mineral and fuel deposits and forests to meet debt obligations.
15 Environmental Justice Belief that racial minorities and members of low income neighborhoods are subjected to disproportionate environmental hazardsHarlem, NY is subjected more air pollutionFactories dump wastes into the Mississippi. This affects the cities along the Mississippi such as New Orleans.
16 Environmental Problems Air PollutionCaused by car emissions and smog in the airCan cause breathing problems such as asthma as well as vision problemsan estimated 700,000 deaths per year could be prevented if air pollutants were cut downWater PollutionCaused by dumping wastes into bodies of water as well as oil spillsNearly 1.1 Billion people lack clean drinking water
17 Global warmingNatural greenhouse gasses such as CO2 are turning the worlds atmosphere into a greenhouse.Results in polar ice caps, fiercer storms, deserts expanding, and devastating droughts.Governments continue to place addressing GW low on their agendaKyoto Protocol169 countries agreed to reduce their emissions of greenhouse gasses.US, produces ¼ of the earths CO2 did not.Is caused by industrial nations, Affects developing nations, they are more likely to have economies based on limited resources.
18 GlobalizationPolluting companies may relocate to countries with less stringent environmental standardsIndustrialization that often accompanies globalization has increased pollutionMultinational Corporations have incentive to consider cost of natural resourcesWasting resources would make little sense
19 How do you think ZPG would affect the US/ world? ?????How do you think ZPG would affect the US/ world?
20 ?????Do You think that an increasing the population would help or harm America/ The World?